Spooled device guide system

ABSTRACT

A technique facilitates coiled tubing operations in offshore environments. The technique employs a spooled device, which is disposed on a reel located on an offshore facility. A guide system is mounted on the offshore facility to guide the spooled device from the reel, along a desired path, and down through the floor of the offshore facility. The guide system enables the coiled tubing job to be conducted without requiring a line of sight along the coiled tubing as it is delivered down through the offshore facility.

CROSS-REFERENCE TO RELATED APPLICATION

The present document is based on and claims priority to U.S. ProvisionalApplication Ser. No. 61/212,556, filed Apr. 13, 2009.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art. Oilproducers use offshore platforms to support subsea oil wells. In manyapplications, coiled tubing jobs are performed on the offshore platform.The coiled tubing is unspooled from a reel and injected through a rigfloor via a coiled tubing injector hanging in a derrick. However, thecoiled tubing reel must be placed in position so that a line of sight ismaintained along the coiled tubing as it moves through a door in the rigfloor.

The line of sight requirement can create a variety of problems relatedto utilization of the offshore platform and completion of the coiledtubing job. For example, crane capability and lift radii restrictionsoften prevent placement of the heavy reel in an optimum position on theoffshore platform. Additionally, placement of rig components, such asautomated pipe handling systems and elevated catwalks, can be difficultwithout blocking the line of sight. Often, large deck areas of theoffshore rig must be segregated with barriers during a coiled tubing jobdue to movement of the coiled tubing pipe overhead. As a result, rigoperations and crane lifts are restricted. Because of the limitations onplacement of the coiled tubing reel and other components, small radiusgoosenecks are sometimes necessary to direct the coiled tubing along adesired route. However, use of small radius goosenecks oftendetrimentally impacts the low cycle fatigue resistance of the coiledtubing.

SUMMARY

In general, the present disclosure provides a system and methodology forfacilitating coiled tubing operations in offshore environments. Thesystem and methodology employ a spooled device disposed on a reel whichis located on an offshore facility. A guide system is mounted on theoffshore facility to guide the spooled device from the reel, along adesired path, and down through a floor of the offshore facility. Theguide system enables the coiled tubing job to be conducted withoutrequiring a line of sight along the coiled tubing as it is delivereddown through the offshore facility.

BRIEF DESCRIPTION OF THE DRAWINGS

Certain embodiments of the invention will hereafter be described withreference to the accompanying drawings, wherein like reference numeralsdenote like elements, and:

FIG. 1 illustrates an embodiment of an offshore facility incorporating aguide system;

FIG. 2 is a view of an embodiment of an offshore platform/rig in which areel is deployed on a lower deck to deliver a spooled device through aguide system;

FIG. 3 is a view of an embodiment of an offshore facility in which aguide system is used to guide coiled tubing from a coiled tubing reel;

FIG. 4 is a view of an embodiment of an offshore facility having a guidesystem mounted along a derrick;

FIG. 5 is a view of an embodiment of an offshore facility with a guidesystem having a swivel to enable alignment with a well center;

FIG. 6 is a view of an embodiment of an alternate example of an offshorefacility with the guide system mounted along a derrick;

FIG. 7 is a view of an embodiment of one example of the offshorefacility having a guide system in which one or more trumpet ends areemployed along the guide system to limit potential stress acting oncoiled tubing delivered through the guide system;

FIG. 8 is a view of an embodiment of a derrick and a tubular guidesystem mounted to the derrick;

FIG. 9 is an overhead view of an embodiment of an offshore facility witha derrick and cooperating guide system;

FIG. 10 is a view of an embodiment of an alternate example of anoffshore facility in which the guide system is utilized to access ablowout preventer impact deck;

FIG. 11 is a view of an embodiment of a portion of the systemillustrated in FIG. 10;

FIG. 12 is another view of an embodiment of a portion of the systemillustrated in FIG. 10; and

FIG. 13 is another view of an embodiment of a portion of the systemillustrated in FIG. 10.

DETAILED DESCRIPTION

In the following description, numerous details are set forth to providean understanding of the present invention. However, it will beunderstood by those of ordinary skill in the art that the presentinvention may be practiced without these details and that numerousvariations or modifications from the described embodiments may bepossible.

The present disclosure generally relates to a system and method forfacilitating offshore well operations in which a spooled device isdeployed from a surface facility. The technique enhances the efficientand safe use of a surface facility, e.g. an offshore platform/rig, asemi submersible rig, a monohull vessel, when deploying the spooleddevice to a subsea well or other location. The spooled device maycomprise coiled tubing, wireline, slickline, or other spoolable devicewhich is deployed from a reel. A guide system is mounted on the offshorefacility to deliver the coiled tubing or other spooled device along apredetermined route in a manner which does not require “line of sight”control over the spooled device as it is delivered down through theoffshore facility to a subsea wellhead or other subsea installation.

Depending on the specific structure of the offshore facility, the guidesystem is designed according to the size, shape, and components of theoffshore facility. In many applications, the guide system comprises atubular guide, such as a pipe, e.g. steel pipe, through which thespooled device is routed. The tubular guide is designed with largeradius curves to reduce or eliminate the fatigue otherwise experiencedby certain spooled devices, such as coiled tubing. The guide system maybe a continuous guide which fully encloses the route along which thecoiled tubing is delivered from the coiled tubing reel to a locationproximate a floor of the offshore facility. In other embodiments,however, the guide system may be intermittent such that the coiledtubing or other spooled device extends through open regions betweentubular sections of the guide system.

In many applications, the guide system is permanently installed on theoffshore facility. For example, the guide system may be mounted duringconstruction of the offshore facility, thus enabling the guide system tobe fully integrated and fitted into the derrick and/or other componentsof the offshore facility. In some applications, the guide system mayincorporate additional components, such as mechanisms to grip and holdthe coiled tubing (or other spooled device) at either end of the guideto increase rig up efficiency. The guide system also may incorporateswivels, extensions, flexible sections, lubricants, trumpet ends, rollerguides, and other components designed to facilitate movement of thecoiled tubing (or other spooled device) along the guide system duringoperation.

By incorporating the guide system into the offshore facility in apreplanned design which cooperates with the overall design of theoffshore facility, the reel, e.g. coiled tubing reel, may be placed in avariety of convenient locations, such as a lower deck location of anoffshore platform. Without the need for line of sight control, the guidesystem may be used to route the coiled tubing in a manner that does notinterfere with pipe handling systems, elevated catwalks, and othercomponents of the offshore facility. Additionally, the guide system canfree up large deck areas of the offshore facility by removing the needto create barrier regions which can restrict rig operations and cranelifts.

Referring generally to FIG. 1, an embodiment of an offshore system 20 isillustrated as having a guide system 22 incorporated into an offshorefacility 24. The offshore facility 24 may comprise an offshoreplatform/rig, a semi submersible rig, a monohull vessel, or otheroffshore facility; however FIG. 1 illustrates an example of an offshoreplatform/rig. In the example illustrated, the offshore facility 24comprises a plurality of decks 26 located at different levels to enclosecomponents or to provide surface area for a variety of components. Inmany subsea applications, the offshore facility 24 comprises a pluralityof cranes 28 which are used to move components onto, off, and around theoffshore facility. Additionally, the offshore facility 24 comprises aderrick 30 which is used to deliver and retrieve components with respectto a subsea wellhead or other installation. In the specific exampleillustrated, at least a portion of the guide system 22 is mounted to thederrick 30.

Guide system 22 simplifies the rig up of a spooled device, e.g. coiledtubing, on offshore installations 24, such as jack up offshoreinstallations. By utilizing guide system 22, a reel 32 may be positionedat a variety of convenient locations on the offshore facility 24. Asillustrated in FIG. 2, the reel 32 may be positioned at a convenientlocation 34 which is out of the way of many components used duringvarious subsea well operations. In the particular example illustrated,reel 32 is located on a lower deck 36 of the plurality of decks 26. Thelower deck 36 of this embodiment comprises a cantilevered pipedeck andis positioned beneath an upper deck/pedestal 38 on which derrick 30 ismounted. However, the reel 32 may be positioned in a variety of otherconvenient locations on the offshore facility 24.

Referring generally to FIG. 3, the reel 32 may be positioned so thatcoiled tubing 40 (or other spooled device) is spooled off the lower sideof reel 32 rather than over the top of the reel. The coiled tubing 40 isdelivered from reel 32 into a tubular guide 42, e.g. a pipe section, ofguide system 22. By way of example, guide system 22 may use tubularguide 42 in the form of one or more pipe sections which extendcontinuously or with interrupted segments from reel 32 through a bottomend of derrick 30 or to another desired exit location. The pipe sectionsof guide system 22 are constructed of suitably sized sections of pipe,e.g. steel pipe, with each section having a desired diameter and length.For some applications, the tubular guide 42 has an outside diameter ofapproximately 5 inches, which is suitable for many types of coiledtubing and other spooled devices 40. The one or more pipe sections 42also may be connected via flanges, e.g. ANSI 150 pound flanges, or othersuitable connectors. To cover a desired route, guide system 22 mayemploy a series of elongated pipe sections 42 arranged along adesignated path through which the spooled device, e.g. coiled tubing 40,travels from the reel 32 to a coiled tubing injector head. If thespooled device is not coiled tubing, e.g. slickline cable or wirelinecable, then the tubing injector head is not necessary.

Additionally, the guide system 22 is formed from suitable materials,e.g. stainless steel, which prevent corrosion and ensure a lowcoefficient of friction as the spooled device 40 passes through theguide system 22. Internal surfaces of the pipe sections 42 may beprepared with low coefficient of friction coatings, lubricants, rollers,or other mechanisms to facilitate movement of the spooled device. Tofurther facilitate consistent, easy movement of the coiled tubing orother spooled device 40, the guide system 22 may be permanentlyinstalled on the offshore facility during, for example, the originalbuild phase. The predesigned, permanent installation enables guidesystem 22 to be fully integrated and fitted into the derrick 30 duringconstruction.

As further illustrated in FIG. 4, guide system 22 may employ pipesections 42 with large radius curves 44 to reduce or eliminate fatigueexperienced by the coiled tubing or other spooled device 40. Guidesystem 22 also may comprise a continuous, enclosed guide or anintermittent guide with straight, unconstrained runs between theintermittent pipe sections 42. In the specific example illustrated inFIG. 4, pipe section 42 of guide system 22 extends from under thecantilever at a position beneath the upper deck or pedestal on which thederrick 30 is mounted. From this lower location of reel 32, the pipesection 42 curves upwardly and runs straight along a corner 46 of thederrick 30 until gently curving inwardly toward a central region of thederrick 30. The pipe section 42 then curves downwardly to a positionwhich enables deployment of coiled tubing 40 through a floor opening ofthe offshore facility 24.

In some applications, the guide system 22 is lubricated. For example,lubricant may be placed along the interior of the one or more pipesections 42 by injecting suitable fluid/chemical products into the guidesystem. The guide system 22 and tubular guide 42 also may be designed toprovide secondary fluid containment in the event of a rupture, e.g. apinhole or pipe separation.

The radii of the large radius curves 44 are selected according to thetype and diameter of the spooled device 40. For example, if the spooleddevice comprises coiled tubing, the large radius curves 44 are designedto accommodate coiled tubing of a desired diameter and material. Aminimum radius of curvature may be calculated or otherwise obtained. Forexample, in the publication SPE22820, K. R. Newman, D. A. Newburn, 1991,a table is provided and lists coiled tubing of several outside diameterswith corresponding equivalent radii of zero plastic deformation.Examples of the coiled tubing outside diameters and corresponding radiiinclude: 1 inch OD-5.08 m radius; 1.25 inch OD-6.35 m radius; 1.5 inchOD-7.62 m radius; 1.75 inch OD-8.89 m radius; 2 inch OD-10.16 m radius;2.388 inch OD-12.13 m radius; and 2.875 inch OD-14.61 m radius. Based onthe desired radius parameters, large radius curves 44 may be designed toaccommodate specific types or ranges of coiled tubing.

Any significant increase in the radius of curvature for the tubularguide 42 of guide system 22 over a normal 72 inch, 100 inch, or 120 inchgooseneck may reduce the plastic deformation and increase the fatiguelife of the coiled tubing 40. The guide system 22 may incorporate spanslarger than the minimum radius for all types of coiled tubingcontemplated, e.g. larger than the minimum radius for 2.875 inch ODcoiled tubing. The guide system 22 also may be designed to minimize thenumber of bends throughout the guide system. Various software models maybe used to evaluate the effect of guide system bends in a given designrelative to the anticipated fatigue life of the coiled tubing.

Referring generally to FIG. 5, guide system 22 also may comprise avariety of components which facilitate routing and control over thespooled device 40. In one example, guide system 22 comprises one or moreswivel connections 48 at one or more points along tubular guide 42. Theswivel connections 48 may be used to orient various features, e.g. anupper gooseneck, to ensure a desired routing of the spooled device 40.Additionally, the swivel connections 48 may be used to move portions ofguide system 22 temporarily out of the way and then back into positionover a wellhead or well center located beneath an opening 50 in a floor52 of the offshore facility 24. The swivel connections 48 also allow atleast portions of the guide system 22 to be moved out of the way of rigoperations when the guide system 22 is not being used.

Guide system 22 also may comprise other components, such as a verticalextension section 54, e.g. a telescopic extension section, which may beused to provide vertical adjustability along the vertical dimension ofderrick 30. Vertical extension section 54 allows the guide system 22 toaccommodate different well control stacks, e.g. blowout preventerstacks, in derrick 30. The guide system 22 may further incorporate avariety of mechanisms to grip and hold the coiled tubing or otherspooled device 40 at either end of the tubular guide 42 to increase rigup efficiency.

In some applications, guide system 22 provides the ability to run acable winch and connector, e.g. a pipe stabbing connector, through thetubular guide 42. The connector is run from an upper portion of thetubular guide 42 to initially stab the coiled tubing 40 (or otherspooled device). Once connected to the coiled tubing 40, the coiledtubing can be returned to the reel 32 in a controlled manner after theoperation has been completed.

Furthermore, the configuration and route of the guide system 22 may berig specific to ensure the day-to-day operation of the rig is notobstructed. The entry point of the guide system 22 adjacent the reel 32may be adjustable to accommodate various positioning of components onthe offshore facility 24. For example, the entry point of the guidesystem may be selected to accommodate different positions of acantilever structure because such a structure can skid from side to sideand/or from forward to aft depending on the location of equipment on theoffshore facility 24.

In FIG. 6, an alternate position of guide system 22 is illustrated. Inthis embodiment, the tubular guide 42 is attached to the corner of thederrick 30 and enters the workspace at a fingerboard height. As furtherillustrated in FIG. 7, the reel 32 may be positioned off the pipedeck,and the tubular guide 42 may incorporate trumpet ends 56 to avoiddamaging the tubular guide pipe 42 during levelwind movement. Thetrumpet ends 56 enable an expanded angle of entry/exit of the coiledtubing or other spooled device 40 into and out of the tubular guide pipe42. In FIG. 8, an embodiment is illustrated in which trumpet ends 56 areemployed to facilitate movement of coiled tubing 40 from a gooseneckregion within derrick 30 into a coiled tubing injector 58. In thisembodiment, the tubular guide 42 is fitted in a manner similar to astandpipe along derrick 30. FIG. 9 provides an overhead view of derrick30 which further illustrates opening 50 and corresponding doors 60 whichmay be used to selectively provide open access over a wellhead or wellcenter 62.

Referring generally to FIGS. 10-13, another embodiment of offshoresystem 20 is illustrated. In this embodiment, guide system 22 isconstructed with an offshore facility 24 and is utilized to access ablowout preventer impact deck 64. As illustrated, guide system 22employs tubular guide 42 to direct spooled device 40 from a positionabove a surface deck 66 to a position beneath the surface deck. Trumpetends 56 may be used to facilitate routing of the spooled device to theinjector head 58 located above the desired well center 62. In thespecific example illustrated, a gooseneck 68 guides the spooled device40 down through the injector head 58, as best illustrated in FIGS. 10and 13.

In this and other embodiments, the tubular guide 42 may comprise aflexible guide section 70, as best illustrated in FIGS. 11 and 12. Theflexible guide section or sections 70 may be employed to ensurecomponent movement does not kink the tubular guide or the spooleddevice, e.g. coiled tubing. For example, the flexible guide section 70may be used to compensate for the movement of a levelwind. By way ofexample, the flexible guide section 70 may be constructed from armored,braided high-pressure hose which is rubber lined and has a limited bendradius controlled by the size of the flexible segment. Additionally,various mechanisms may be used to reduce friction and wear on thespooled device 40 as it moves through flexible guide section 70 and/orother sections of tubular guide 42. As discussed above, a variety offluids and lubricants may be employed in the tubular guide. However,roller guides 72 and/or other friction reducing mechanisms can beemployed along the route established by guide system 22.

Guide system 22 may be incorporated into a variety of offshorefacilities 24, including semi-submersible vessels, variousplatforms/rigs, and monohull vessels. The guide system 22 is useful incompensating for injector head movement when a heave compensation systemis employed. In some embodiments, the guide system 22 is designed tofacilitate coiled tubing intervention on jack up rigs without runningthrough the rig floor. This type of embodiment may be utilized when acoiled tubing operation is being conducted simultaneously whiledrilling. In any of these applications, the guide system 22 enablesrouting of the spooled device from the location of reel 32 to theinjector head 58 in a convenient manner which avoids the need for lineof sight spooling.

By incorporating the guide system 22 into the offshore facility 24, theroute of the tubular guide 42 may be predetermined and selected to avoidrestrictions, thereby obviating the need for roller guides or otherfeatures to bypass restrictions on the offshore rig/platform. The guidesystem 22 also may be used with wireline or slickline interventions onoffshore installations and it may be used to eliminate the requirementfor multiple sheaves during rig up preparation when performing at leastone well service operation, such as, but not limited to, a coiled tubingoperation, logging operation, slickline operation solid rod conveyanceoperation (for logging), stimulation operation, or similar well serviceoperation, as will be appreciated by those skilled in the art.

It should further be noted that guide system 22 may be employed with avariety of offshore facilities having many types of components. Thesize, length and routing of the guide system may be adjusted accordingto the specifics characteristics of a given offshore facility.Additionally, components such as those discussed above may beincorporated into the guide system to facilitate movement and long-termoperation of the spooled device in a given subsea application.

Accordingly, although only a few embodiments of the present inventionhave been described in detail above, those of ordinary skill in the artwill readily appreciate that many modifications are possible withoutmaterially departing from the teachings of this invention. Suchmodifications are intended to be included within the scope of thisinvention as defined in the claims.

1. A system for deploying coiled tubing, comprising: an offshore righaving an upper deck, a lower deck, and a derrick extending upwardlyfrom the upper deck; a coiled tubing reel mounted on the lower deck; anda coiled tubing guide positioned to route coiled tubing from the coiledtubing reel, past the upper deck, up along the derrick, and back downthrough a lower end of the derrick.
 2. The system as recited in claim 1,wherein the coiled tubing guide comprises a pipe.
 3. The system asrecited in claim 1, wherein the coiled tubing guide is permanentlyinstalled on the offshore rig.
 4. The system as recited in claim 1,wherein the coiled tubing guide is continuous from the coiled tubingreel to the lower end of the derrick.
 5. The system as recited in claim1, wherein the coiled tubing guide is intermittent from the coiledtubing reel to the lower end of the derrick.
 6. The system as recited inclaim 1, wherein the coiled tubing guide is adjustable in length.
 7. Thesystem as recited in claim 1, wherein the coiled tubing guide comprisesa swivel.
 8. The system as recited in claim 1, wherein the coiled tubingguide comprises a trumpet end to reduce stress on coiled tubing movingthrough the coiled tubing guide.
 9. The system as recited in claim 1,wherein the coiled tubing guide is lubricated with a fluid.
 10. A systemfor guiding, comprising: a spooled device disposed on a reel located onan offshore facility; a wellhead for receiving the spooled device; and atubular guide system positioned between the reel and the wellhead toenable use of the spooled device without requiring a line of sightcontrol of the spooled device as it is delivered through the offshorefacility to the wellhead.
 11. The system as recited in claim 10, whereinthe offshore facility comprises an offshore rig platform installation.12. The system as recited in claim 10, wherein the offshore facilitycomprises a semi-submersible rig.
 13. The system as recited in claim 10,were in the offshore facility comprises a monohull vessel.
 14. Thesystem as recited in claim 10, wherein the spooled device comprisescoiled tubing.
 15. The system as recited in claim 10, wherein thetubular guide system comprises a steel pipe through which the spooleddevice moves.
 16. The system as recited in claim 10, wherein the tubularguide system comprises a continuous pipe from the reel to the wellhead.17. The system as recited in claim 10, wherein the tubular guide systemis routed to a blowout preventer impact deck.
 18. A method, comprising:locating a reel with a spooled device on an offshore facility; mountinga guide system on the offshore facility to guide the spooled device; andorienting the guide system to deliver the spooled device through anopening in a floor of the offshore facility without requiring a line ofsight along the spooled device when it is moved through the opening inthe floor.
 19. The method as recited in claim 18, further comprisingunspooling the spooled device from the reel and guiding the spooleddevice via the guide system.
 20. The method as recited in claim 18,wherein locating comprises locating the reel on a lower deck of anoffshore platform.
 21. The method as recited in claim 18, whereinmounting comprises permanently mounting an enclosed guide system onto anoffshore platform.
 22. The method as recited in claim 18, whereinlocating comprises locating a coiled tubing reel.
 23. The method asrecited in claim 18, wherein mounting comprises mounting a tubing upalong a side of a derrick and down through a central, lower end of thederrick.
 24. The method as recited in claim 18, wherein orientingcomprises pivoting a portion of the guide system to a desired position.